In recent years, as a fine pattern formation technique that replaces photolithography, a pattern formation technique that uses an imprint method is attracting attention. An imprint method is a pattern formation technique in which one-to-one transfer of a fine structure is performed by using a mold member (mold) having a fine uneven structure to transfer the uneven structure to a molded resin. For example, in an imprint method in which a photocurable resin is used as the molded resin, droplets of the photocurable resin are supplied to the surface of a transfer substrate, a mold having a desired uneven structure and the transfer substrate are brought close to each other until a distance therebetween becomes a predetermined distance, and the uneven structure is thereby filled with the photocurable resin. In this state, light is emitted from the side of the mold to cure the photocurable resin and, thereafter, the mold is separated from the resin layer. As a result, a pattern structure having an uneven structure (uneven pattern) in which projections and depressions of the mold are inverted is formed. Furthermore, imprint lithography is performed in which a transfer substrate is etched by using the pattern structure as an etching mask. In imprint lithography, as the transfer substrate, a transfer substrate provided with a material layer for a hard mask on the surface thereof may be used. In this case, the material layer for a hard mask is etched by using a resin layer formed by the imprint method as an etching mask to form a hard mask, and the transfer substrate is etched by using the hard mask as an etching mask.
When manufacturing a mold used in such an imprint method, usually, an electron beam-sensitive resist is applied to a base for the mold and a resist pattern is formed by performing electron beam drawing on the resist. Subsequently, an uneven pattern is formed by etching the base by using the resist pattern as an etching mask to manufacture the mold. However, electron beam lithography that uses electron beam drawing requires the use of an expensive drawing apparatus and takes a long time to complete the drawing, and hence there has been a problem in that the manufacturing cost of the mold increases. In addition, when a foreign object enters between the mold and the transfer substrate during imprinting, both the mold and the transfer substrate are significantly damaged, which makes it difficult to reuse the damaged mold. Hence, there is a problem in that the costly mold manufactured by electron beam lithography is lost.
To cope with this, a duplicate mold (hereinafter referred to as a replica mold) is manufactured by imprint lithography using an imprint method from a master mold, the master mold being a mold manufactured by electron beam lithography (PTL 1 and the like).